The present disclosure relates generally to semiconductor manufacturing processes and in particular to a method for manufacturing a semiconductor device using a modified photoresist in the semiconductor manufacturing process.
Conventional photoresists tend to form a carbon ‘crust’ on their surface in response to being exposed to an ion implantation step in the integrated circuit manufacturing process. Removing this carbon-crusted photoresist can raise a number of issues. There are two methods for removing the photoresist from the substrate after it has been exposed to the ion implantation step. One method for removing the photoresist from the substrate involves both dry etching followed by wet etching. The dry etching step tends to remove the carbon crust that has formed on the photoresist, while the wet etching step removes any of the photoresist not removed during the dry etching. However, dry etching may require using a plasma (e.g., O3, CF4, etc.) that can damage the ion implanted substrate due to, for example, oxide loss, and result in a reduced electrical performance and yield. A solution to this problem involves wet etching without the substrate-damaging dry etch. Such a method can prevent the substrate damage discussed above, but typically suffers from the failure of the wet etching to remove all of the carbon crust that formed on the photoresist during the ion implantation process. This left-over carbon crust can remain on the substrate and influence electrical performance and/or cause defects in the semiconductor device.